A number of industries make use of a work area in which wheeled units are worked on. Typically a garage or other workspace for car maintenance, repair or construction needs to be able to access a vehicle from any direction. In order to work on the underside of the vehicle there is a need for a pit over which the vehicle can be place to enable an operative to enter the pit to access the underside of the vehicle. With a vehicle in place over a pit opening so as to fully cover the opening then inadvertent falling is prevented. However, once the vehicle is removed from the pit opening, the pit opening becomes a hazard until some form of barrier is put in place.
Various methods have been used to prevent inadvertent entry into such a pit. These include a vertical barrier extending around the pit periphery or baulks of timber inserted to lie on a rim about the pit opening so as to be flush with surrounding floor area. However, these methods require action by somebody and take time to carry out. In addition, if the person working in the pit on a vehicle subsequently climbs out and the vehicle is moved away from the pit, the pit opening is left unguarded until a person arrives to rectify the situation. Whatever physical barrier is used can be supplemented by signs, lights or sounding means.
In our co-pending application PCT/GB2009/050460 there is described a retractable safety device for use in regulating entry to a hazard area from an access area comprising: a parallel array of members each member in the array having—a first end pivotally attached to a first side rail to which each member is pivotally attached by a first end of each array member; a second side member to which each member in the array is pivotally attached by a second end of each array member; the array and first and second side arrays being displaceable in a plane between a first, working, configuration in which the first and second side members are relatively wide apart; and a second, stowage, configuration where the first and second side members are relatively close; at least two slide arms, each slide arm being located on, and pivotally connected to, the second side member; the slide arms being spaced apart on the second side member; a slider mounted on each side arm adapted to slide along the slide arm on which it is mounted, each slider including means whereby the slider can be secured to a region in or near the hazard area so as to permit the slide arm to be displaceable relative to the slider; and stop means to limit the extent of travel of the slide arm relative to the slider so as to define the second, stowage, configuration; the device providing that with the array in the first, working, configuration the array serves to obstruct passage from the access area into the hazard area; and with the array in the second, storage, configuration the array is withdrawn from obstructing passage from the access area into the hazard area. Hereafter, a safety device of this type will be referred to a being ‘of the type described’.
When a vehicle covers and entire pit opening, then it provides a complete barrier to inadvertent pit entry. However, access to the pit for work on the vehicle is also prevented. In the event a vehicle covers only a party of the pit opening, access to the pit to work on the vehicle is readily available but the exposed section of the opening remains a hazard.